Benchmark: JavaScript spread operator vs Slice performance

Tests:

Using the spread operator
const firstObject = [{ sampleData: 'Hello world' }] const secondObject = [{ moreData: 'foo bar' }] const finalObject = [ ...firstObject, ...secondObject ];
Using Object.assign
const firstObject = [{ sampleData: 'Hello world' }] const secondObject = [{ moreData: 'foo bar' }] const finalObject = firstObject.slice().concat(secondObject.slice())

Rendered benchmark preparation results:

Previous results

Test case name	Result
Using the spread operator
Using Object.assign

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Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:99.0) Gecko/20100101 Firefox/99.0

Browser/OS: Firefox 99 on Windows

Test name	Executions per second
Using the spread operator	14323720.0 Ops/sec
Using Object.assign	7433848.0 Ops/sec

JavaScript spread operator vs Slice performance (version: 0)